But Lilly's marketing of fluoxetine has been so strong that it may actually remain competitive with its imitators.

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Barr will probably have exclusive rights to the generic fluoxetine, the chemical name for Prozac, for six months.

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Your doctor may prescribe one of several selective serotonin reuptake inhibitors (SSRIs), such as sertraline (Zoloft), paroxetine (Paxil) or fluoxetine (Prozac), to help delay ejaculation.

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Launching fluoxetine as a brand-new drug allows Lilly to reach women and their physicians in a way that new publicity for the Prozac brand won't.

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In addition to selling the once-a-week Prozac, Lilly has also re-branded fluoxetine, the active chemical in Prozac, to treat a serious form of premenstrual syndrome.

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But instead of simply marketing Prozac to women with PMDD, Lilly has decided to launch fluoxetine hydrochloride, the chemical formerly known only as Prozac, as a brand-new drug called Sarafem.

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The patent on the fluoxetine hydrochloride, the compound formerly known only as Prozac, runs out next year, and the patent on the process used to make it runs out in 2003.

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For some, the illness is a medically treatable imbalance in brain neurochemistry a serotonin deficiency that can be remedied by selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, better known as Prozac, which has been prescribed to more than 35m people worldwide since its launch in 1988.

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Some research associates use of citalopram, fluoxetine and sertraline with a rare but serious newborn lung problem (persistent pulmonary hypertension of the newborn, or PPHN) when taken during the last half of pregnancy, as well as heart defects affecting the septum the wall of tissue that separates the left side of the heart from the right side of the heart.

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